Its a steering wheel.. It has an arc which looks like a part of a perfect circle..
And also, the veins on D’s are mostly straight and random in symmetry, the veins in the picture are too curved and almost perfect in symmetry.
The veins on the steering is due to ageing of the polymer used in making the steering, which is brought about by constant changes in temperature and pressure.
Also the position of the subject in relation to the veined object is not consistent with the organ’s position on the body. His D will have to be at least half a meter long to be able to take that pic of it from that position.
If there was anyone with that Big of a D, I think I would’ve heard about it.
The last I checked, world record was still 9″ flacid. ☺